When Blake Shelton hosted Saturday Night Live last January, the writers cooked up a burlesque of a country music video. Judging from the wig and wardrobe choices, he and cast members Kate McKinnon and Aidy Bryant were meant to be facsimiles of Alan Jackson, Reba McEntire and Wynonna Judd, three veteran country stars teaming up on an inspirational ballad. For comedic effect, the actors brought hammy over-singing and folksy showbiz gloss to lyrics that exhorted listeners to embrace the metaphorical western boot of wish fulfillment within them, or some such hokum. As way-out as the sketch was, it leaned on a familiar perception of country music — one that's received plenty of other pop culture reinforcement.

Numerous country-singing contestants have held their own on the stages of American Idol and The Voice, where formidable voices and dramatic performances rule. Who can forget that it was Idol that launched Carrie Underwood? Ever since sweeping season four, she's been admired and beloved by audiences because of how she uses those powerhouse pipes of hers. By flexing her technical ability and telegraphing emotional and physical exertion with every boldfaced ballad and stomping kiss-off, she's embodied what many have long considered the country-pop singing ideal. If few other country singers have approached the athleticism of Underwood's instrument, many contemporary hit-makers in her format have built popular sounds on vigorous vocals and a muscled-up modern rock guitar attack. All of this has contributed to country music's reputation as powerfully hearty stuff, dedicated to the display of sincerity and showmanship — to making a show out of meaning it.

Lately, though, the tone of some mainstream country singing and songwriting has begun to relax considerably. "My Church," a breezy slice of irreverence that just cracked the Top 5 of Billboard's Hot Country Songs chart, is well on its way to establishing 25-year-old Maren Morris as a new breed of country-pop star. She sings low during the verses; there's a world-weary slouch to her enunciation, a coolness to her affect. But even when she scales the octave-higher hook, she's far from belting. "In some of her choruses, she does actually sing in some range areas that are similar to a Carrie Underwood performance," notes vocal coach Sophie Shear, who works with budding singers in a variety of styles, country included, in her Nashville studio. "However, she's not exerting; she's not pushing quite as much. ... So our brains perceive Maren as a more relaxed singer, even if they're singing the same notes."

Just a few weeks ago, the duo Brothers Osborne scored a kindred Top 5 hit of its own with the Grammy-nominated, groove-driven roots-rock number "Stay a Little Longer," a song put across by 32-year-old singer T.J. Osborne's rhythmically relaxed phrasing and capped off by 34-year-old John Osborne's extended guitar jam. Both the Osbornes and Morris are among the most buzzed-about acts in the format right now, and they're not the only ones giving country a more casual tone of voice. Also high on the charts are follow-up hits from Sam Hunt and Kelsea Ballerini, who've each had major country hits within the last year. Hunt is known for skating between R&B-indebted crooning and conversational rapping; Ballerini for her flip, self-possessed take on flirtation. And for every artist who's managed to score a hit in this vein, there are several others working toward a breakthrough, like Haley Georgia, who employed a winkingly acidic sung-spoken delivery on last year's "Ridiculous," multi-talented Clare Dunn, who brings a clipped, staccato swagger to her current single "Tuxedo," and newcomer Russell Dickerson, who works territory next door to Hunt's in "Yours."

There were signs of younger artists bringing a new casualness to country as far back as the summer of 2012, when Taylor Swift began sharpening the edges of her conversational delivery with one foot still firmly planted in Nashville. One of the most striking things about her single "We Are Never Ever Getting Back Together" was the way her lyrics and vocal inflections conveyed millennial exasperation. Kacey Musgraves' debut single "Merry Go Round" arrived just a month later, introducing a young singer-songwriter who laced her work with reticent wit. What really grabbed attention, and convinced many music critics to anoint her country's socially progressive savior, was the subtle thumbs-up to same-sex attraction in her third single "Follow Your Arrow." Not that she presented her perspectives as being in any way radical for a twenty-something. To the contrary: one of the defining qualities of her songwriting voice is how thoroughly low-key it is. And in that way, she and Hunt share common ground; the way he broods over conflicted emotions in songs like "Take Your Time" and "Break Up In a Small Town" is, likewise, artfully mellow.

By the time the Country Music Association awards rolled around last November, the nonchalance of Hunt's vocal delivery had had enough of an impact within the industry to merit a joke from the show's co-hosts, Underwood and Brad Paisley. During the opening monologue, Paisley began to lurch erratically between talking and singing, setting Underwood up to ask what he was doing. Then came his droll punch line: "I'm Hunting — Sam Hunting. You know, how he talks in his songs and then suddenly for sorta no reason starts singing, and the younger demographic just totally eats it up."

When the next award show rolls around, Paisley could very well be cracking wise about the even-tempered appeal of Texas-bred Morris or the Maryland-born Brothers Osborne. The latter released their rewarding full-length debut Pawn Shop in mid-January on the heels of "Stay a Little Longer," which serves as a good introduction to the sound they've achieved with super-producer Jay Joyce. For the better part of a decade, Joyce has been nudging mainstream country toward both live wire looseness and meticulous studio craft with his work on Eric Church and Little Big Town albums, in the process laying groundwork for the production and arrangement side of this trend. Joyce's way with digitally taut, down-home funkiness is central to the Osborne's easeful, pop-friendly sonic identity. John's extended vamp, worlds away from the contemporary country norm of aggressively streamlined guitar solos, fills a sizable chunk of his duo's hit. He teases a coiling, syncopated guitar figure into sprightly, note-bending runs, which stealthily taper off before bounding back. Patience is central to his playing style; he'd rather toy with the beat than attack it forcefully. "A lot of times there's this big misunderstanding that if something is rocking or grooving, it has to be loud," John offers, reclining on a couch next to his younger brother in an office space maintained by their management company. "I don't know where that happened along the way. It's like everyone's screaming for attention or something. But I mean, if you listen to a B.B. King record, it's just groove. If you listen to a Marvin Gaye record, those guys aren't playing loud. It's really laidback."

Capitol Nashville's VP of A&R Autumn House — who's been involved with the Osbornes since before they were signed to the label — feels the descriptor "laidback" also fits the brothers themselves. "They do energy in a different way," she says on the phone. "Their influences are probably a little bit more rooted in that laidback place, The Band and The Allman Brothers and that kind of thing. ... I think if you grew up in a household that was playing that music, there might be some nostalgia for hearing those sounds again [from] two very current millennials."

In "Stay a Little Longer," T.J.'s vocal performance feels no more hurried than the instrumental accompaniment. Elsewhere on the album, his phrasing and enunciation grow even more elastic, his delivery occasionally taking on a slyly poker-faced quality. In "Rum," he coolly elongates his syllables. In the album's title track, his low-pitched drawl drags across the cavernous depths of his range. "He is naturally falling in to a lower register," notes Shear, the vocal coach. "His vocal chords are really thick. He's got a very big chest voice, a large larynx. He's using his natural abilities really well in just kind of talking through some of his words." Watch him sing up close, and you'll find he looks like he's barely even opening his mouth. "And that's probably not something he's doing with a lot of intention," Shear wagers. "He's probably just trying to keep it cool."

In their songwriting, the Osbornes tackle some familiar country themes — booze; making the best of modest means; stoking the heat of a hookup — but tend toward wry understatement. Where country songs that champion small-town ways of life have often been defiant in posture, their bravado registering resistance to classist condescension, the brothers' nods to budget-priced whiskey and junky old cars rusting in the yard come off more as playful, unperturbed, even a little bit arch. That easygoing writerly voice goes hand in hand with their sound.

It's taken a number of years for the Osbornes' sensibilities to align with the mainstream country vanguard. As teenagers in Deale, Md., they played many a grueling set in a bar band with their dad before moving to Nashville, where they separately weathered failed bands, short-lived publishing deals and guitar tech and side man gigs before committing themselves to their songwriting and performing duo. After developing their repertoire, they watched as first a 2013 single, then a 2014 EP barely made ripples in the marketplace. "What we do now, what our album Pawn Shop is, is just the music that we play," says T.J. "We didn't compromise anything. ... It's funny to see how country music has progressed so much in the past five years. When we started playing, [what we were doing] was definitely very progressive. We were doing songs that were, in my mind, pretty far ahead of what a lot of people were doing at the time. So I think things kind of caught up to what we were doing."

As young as she is, Morris's breakthrough moment was a long time in the making, too. She came to Nashville with a decade of experience independently releasing albums and gigging in and around the Dallas-Fort Worth-Arlington area. Then she put her recording career aside to focus on learning the collaborative, professionalized craft of Music Row songwriting. Songs that she co-wrote made it onto albums by Tim McGraw and Kelly Clarkson. Gradually, though, Morris accumulated material for a project of her own. "I found my voice in those writing rooms," she explains, perched on a bar stool at a neighborhood pub. "I started to just hear this voice. It was my voice, but also — I didn't know it at the time — just a point of view and identity behind these songs that was this quiet confidence. I feel like I would describe myself as [having] that, because I'm not the person capturing the attention at a party."

Morris made the savvy decision to self-release her EP through Spotify last fall, and the response it received — 2.5 million streams within weeks — motivated her now-label Columbia Nashville to rush "My Church" to country radio and commission her addictive upcoming album, Hero. (Morris co-produced it with busbee, whose past credits bridge country and pop.) In "My Church," Morris shrugs off the notion that choosing to cruise to the car radio rather than warm a pew makes her a heathen. And it's hard to imagine a franker, more coolheaded breakup speech than the one she gives in "I Wish I Was," a youthful angle on Bonnie Raitt-style, R&B-pop balladry: "Go on hate me if you have to," she insists. "I hate myself too." During a recent performance at the Ryman Auditorium, she introduced it as a song for those who "can relate to being a bad guy." That and "Company You Keep" — a toast to the idea that it's the people, not the poshness of the setting, who make the party — are about as close as she gets to romance on her EP.

She expands her low-stakes perspective on love on the new album, likening a hookup to a bad habit too trivial to kick (the flippantly, fluently syncopated "Just Another Thing") and acknowledging a distrust of mushiness (the wistful ballad "I Could Use a Love Song"). In the chorus of the latter, she articulates a clear-eyed, decidedly twenty-something perspective. "I could use a love song," she sings, but she's not looking for just any sweet, little ditty. What she wants is to be transported back to a dreamier time "when I wouldn't roll my eyes at a guy and a girl who make it work in a world that, for me, so far, just seems to go so wrong."

In person, Morris explains, "I see this gap happening in the market where the only time I hear a girl sing on the radio, it's a love song — or it's like a 'fuck you' love song. I felt like I live in the middle of those worlds, where I don't wanna feel extreme in either way. It's OK to be a young adult in [your] 20s and not have to worry about getting married or getting pregnant, having a baby. I'm in that window right now." She goes on, "Not to say that I don't love songs that are a kiss-off or a great love song. I'm not trying to bash that at all. I think just where my head was at when we wrote this record, I wasn't there and I didn't want to feel like I had to be. ... You can be honest without being earnest."

Morris proves her point in the girl group pop update "Drunk Girls Don't Cry." "It's bulls*** and you know it," she sings. "Yeah, I see it in your eyes every time that you tell me deep down he's a really good guy."

"She speaks to you in a way that is relatable," observes Carla Wallace, co-owner and GM of Morris's publishing company, Big Yellow Dog Music. "It's like you're her best friend." Wallace jokingly compares Morris's appeal to that of Rizzo, the tough-talking, streetwise female ringleader in Grease. "She's just cool as s***," laughs Wallace. "You want to smoke a cigarette with her, even if you don't smoke."

That effect is only enhanced by Morris's delivery of "Drunk Girls." Between the unfussy resolve of her enunciation and the way she milks the lower part of her range, it's the aural equivalent of an eye roll. Says Shear, "We're noticing more of a demand for almost kind of a masculine vocal sound, lower pitches, slower vocal movements, what we call vocal fry, which is basically a slower vibrational speed of the vocal chords." But as Shear is careful to point out, the country mainstream is hardly the only segment of the pop music landscape where youthful vocal approaches are evolving away from "polish." "I think smoother, cleaner and 'prettier' kinds of sounds, they just remind us of an older generation," she says.

The thing is that the country radio format is deliberately aimed at a multi-generational audience — say, kids fresh out of high school, their empty-nesting parents and young professionals and working folks who fall in between. There's a continual give-and-take between the tastes of different age groups while new aesthetic contributions get combined with countrified conventions and absorbed into the mélange by adaptable artists. The rise of this casual posture is one of many signs of a new shift in mainstream country's center of gravity — a shift toward youthful negotiations of the divide between resilient small-town identity and plugged-in, 21st Century fluidity. Even country stars who established themselves as robust performers years ago, like Underwood and Dierks Bentley, are experimenting with different vocal approaches. In Bentley's current single, "Somewhere on a Beach," he strikes a cavalier posture with his loosened phrasing, and in Underwood's ballad "Heartbeat" — featuring harmonies from Hunt and recorded with his cowriter-producer Zach Crowell — she comes on more coyly than you'd expect until the titanic chorus.

There's an element of skill involved in an artist recalibrating the tone of her expression, just as it requires skill to massage a naturally laidback musical approach into mainstream appeal. It's worth noting that leading up to their success, Morris and the Osbornes — along with Musgraves, her guitarist Misa Arriaga, Idol runner-up Kree Harrison, hot-picking country singer Charlie Worsham, British pop chanteuse Lucie Silvas, who's now married to John Osborne, and numerous others — were part of a circle of young songwriters who were proud to claim the bohemian enclave of East Nashville, the symbolic antithesis of the country music industry headquartered just across the Cumberland River, as their home turf. "East Nashville's kind of the quirky part of Nashville," John Osborne explains. "There's a lot of originality here. A lot of artists are over here. It's just kind of a breeding ground for people that want to be individuals. ...Even though it's only, like, a five minute drive from Music Row [the neighborhood where recording industry power has historically been centralized], you're able to kinda get out of the music business world for a little bit and just live in a town."

If the division between those two worlds has never truly been as tidy as it's made out to be, learning to straddle them surely furthered Morris and the Osbornes' development as artists bent on mastering and cleverly tweaking country's formulas and on packaging their distinct voices and vantage points for a popular audience. Important musical experimentation — or what T.J. Osborne calls "some of the most creatively fertile moments of my life" — happened while they were just hanging out at somebody's house, layering snippets of melodies, lyrics and licks with a looping pedal, teasing offhand ideas into expansive productions.

What they're bringing into the mainstream with them now is a different angle on one of country's core values: authenticity. They work to make it feel like their fully realized performances still retain some of the conversational qualities of living room jams. For a new generation of music-makers, that's a subtler way of signaling that they mean it.